Plate material conveying device

ABSTRACT

The present invention provides a plate material conveying device including a compact traveling member to enable an increase in plate material conveyance speed and a reduction in time required for acceleration and deceleration and to allow small plate materials to be more efficiently conveyed, the plate material conveying device further enabling one of a gripper and a suction type plate material holder to be selected for conveyance of a plate material. Traveling members  13, 14  are provided on respective tracks  11, 12  so as to travel freely along the respective tracks  11, 12.  Each of the traveling members  13, 14  has a plate material holder support frame  21, 22  supporting suction type plate material holders  23 A,  23 B,  23 C. The plate material holder support frame  21, 22  has a frame main body  21   a,    22   a,  and a turning frame  21   b,    22   b  which is turnable in a substantially horizontal direction with respect to the frame main body  21   a,    22   a  and which is turnable to a position where the supported plate material planarly overlaps the adjacent track. Each of the turning frames  21   b,    22   b  has a gripper  60  gripping an end of the plate material. An opening of the gripper is configured to face a central side of the plate material.

FIELD OF THE INVENTION

The present invention relates to a plate material conveying device that carries raw plate materials into a plate material processing machine and carries out product plate materials processed by the plate material processing machine as well as remainder materials.

BACKGROUND OF THE INVENTION

In a plate material conveying device of this kind, a plurality of plate material holders are provided on a traveling member traveling along a predetermined track, to hold and covey plate materials (for example, the Unexamined Japanese Patent Application Publication (Tokkai) No. 2000-351032). The plate material holders are composed of, for example, suction pads and can hold and release a plate material. In general, the plate material holders are arranged so as to cover the largest one of the plate materials to be conveyed. A special plate material conveying device is described in the Unexamined Japanese Patent Application Publication (Tokkai) No. 2000-117373. The plate material conveying device is configured such that the distance between the plate material holders can be varied depending on the size or shape of the plate materials.

To stably convey a plate material, the plate material holders preferably hold the plate material in the vicinity of the edge thereof over a wide range. Thus, many plate material holders need to be arranged over a wide range, resulting in a large holder array member composed of the plate material holders and a support frame for the plate material holders. This applies not only to common plate material conveying devices but also to the one described in the Unexamined Japanese Patent Application Publication (Tokkai) No. 2000-117373. The large holder array member increases the weight of the plate material conveying device itself and prevents an increase in the speed of the traveling member and a reduction in time required for acceleration and deceleration.

Thus, an attempt has been made to provide a plurality of traveling members each having a holder array member and cooperatively conveying a plate material. This configuration enables a reduction in the size of the holder array member in each of the traveling members. This in turn allows an increase in the speed of the traveling members and a reduction in time required for acceleration and deceleration. Furthermore, for relatively small plate materials, the traveling members individually convey the respective plate materials. This allows conveyance efficiency to be drastically improved.

Requirements for achieving the above-described attempt are as follows. The traveling members need to travel along different, parallel tracks so that the two adjacent traveling members can pass each other while preventing the holder array members from interfering with each other. Furthermore, the holder array members of the traveling members need to be able to stably hold a common, large plate material. Additionally, when the traveling members individually convey the respective plate materials, each of the traveling members needs to be able to hold any of the plate materials. The traveling members further need to be easily controllable. Therefore, a technique for achieving these requirements needs to be developed.

Furthermore, when remainder materials resulting from cutting-out of workpieces from raw plate materials are carried out, suction type holders may fail to hold the remainder materials. Thus, a plate material conveying device in which a plurality of traveling members cooperatively convey plate materials needs to provide the function of allowing a gripper to grip the plate materials during conveyance.

SUMMARY OF THE INVENTION

An object of the present invention is to solve the above-described problems and to provide a plate material conveying device including a compact traveling member to enable an increase in plate material conveyance speed and a reduction in time required for acceleration and deceleration, and to allow small plate materials to be more efficiently conveyed, and also the plate material conveying device enable one of a gripper and a suction type plate material holder to be selected for conveyance of a plate material.

Another object of the present invention is to enable remainder materials with the inside thereof cut out to be conveyed and to allow the conveyed remainder materials to be smoothly stacked in a remainder material yard.

Yet another object of the present invention is to enable the remainder materials or the like to be stably conveyed even if the remainder materials are large in size.

The plate material conveying device includes a plurality of tracks, and a first traveling member and a second traveling member which are provided on the respective tracks so as to travel freely along the respective tracks. Each of the traveling members has a plate material holder support frame supporting plate material holders sucking and holding a plate material. The plate material holder support frame has a frame main body, and a turning frame which is turnable in a substantially horizontal direction with respect to the frame main body and which is turnable to a position where the supported plate material planarly overlaps the adjacent track. Each of the turning frames has a gripper gripping an end of the plate material. Grip openings of the grippers of the first traveling member and the second traveling member are configured to face a central side of the plate material.

According to this configuration, the two traveling members, which can travel independently, are installed on the respective tracks, installed parallel to each other between a plate material processing machine and a plate material placement portion. A large plate material is conveyed cooperatively by the plate material holders of the two traveling members. A relatively small plate material is conveyed independently by the plate material holder of each of the traveling members. This configuration enables a reduction in the size of the traveling member. This in turn allows an increase in the speed of the traveling member and a reduction in time required for acceleration and deceleration. Furthermore, since each of the traveling members independently conveys the plate material, conveyance efficiency can be improved.

The plate material conveying device also has the grippers. Thus, not only the suction type plate material holders can hold the plate material but also the grippers can grip the plate material at opposite ends thereof in a transfer direction during conveyance. Consequently, even remainder materials with the inside thereof cut out can be conveyed. The gripper is provided on the turning frame of each of the traveling members. Thus, even large-sized remainder materials or the like can be conveyed.

In the present invention, the plate material may be a remainder material with inside thereof cut out. The first traveling member and the second traveling member may travel to convey the plate material that is the remainder material to a remainder material yard and then stack the remainder material on top of other remainder materials.

When the plate material is the remainder material, the suction type plate material holder may fail to hold the plate material. In this case, the grippers grip the plate material at the opposite ends thereof in the transfer direction to allow the remainder material to be easily carried out to the remainder material yard. Furthermore, since during carrying-out, the remainder material is gripped by the grippers at the opposite ends thereof in the transfer direction, the carried-out remainder material is prevented from being caught on the remainder materials stacked in the remainder material yard. The remainder material can thus be smoothly carried out.

In the present invention, the gripper may be provided on the frame main body of the plate material holder support frame of each of the traveling members. The plate material may be gripped by at least a total of four grippers provided on the frame main body and the turning frame of the plate material holder support frame of each of the traveling members.

As described above, the plate material is gripped by at least a total of four grippers provided on the frame main body and the turning frame of the plate material holder support frame of each of the traveling members. Then, each of the opposite ends of the plate material can be gripped by at least two grippers with a sufficient separation distance maintained between the grippers. As a result, even large plate materials can be stably conveyed. Furthermore, even large plate materials with the inside thereof cut out can be carried out.

The plate material conveying device includes the plurality of tracks, and the first traveling member and the second traveling member provided on the respective tracks so as to travel freely along the respective tracks. Each of the traveling members has the plate material holder support frame supporting the plate material holders sucking and holding the plate material. The plate material holder support frame has the frame main body, and the turning frame which is turnable in the substantially horizontal direction with respect to the frame main body and which is turnable to the position where the supported plate material planarly overlaps the adjacent track. Each of the turning frames has the gripper gripping the end of the plate material. The grip openings of the grippers of the first traveling member and the second traveling member are configured to face the central side of the plate material. Thus, the holder array member of each of the traveling members can be made compact. This enables an increase in plate material conveyance speed and a reduction in time required for acceleration and deceleration. Furthermore, small plate materials can be more efficiently conveyed. Additionally, one of the gripper and the suction type plate material holder can be selected for conveyance of a plate material. Even the plate material that is a remainder material with the inside thereof cut out can be conveyed.

The plate material may be the remainder material with the inside thereof cut out. The first traveling member and the second traveling member may travel to convey the plate material that is the remainder material to a remainder material yard and then stack the remainder material on top of other remainder materials. In this case, the carried-out remainder material is prevented from being caught on the remainder materials stacked in the remainder material yard. The remainder materials can thus be smoothly stacked in the remainder material yard.

The gripper may be provided on the frame main body of the plate material holder support frame of each of the traveling members. The plate material may be gripped by at least a total of four grippers provided on the frame main body and turning frame of the plate material holder support frame of each of the traveling members. In this case, even the remainder material or the like which is large in size can be stably conveyed.

Other features, elements, processes, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the present invention with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a plate material processing system including a plate material conveying device according to an embodiment of the present invention.

FIG. 2 is a side view of traveling members and holder array members in the plate material conveying device.

FIG. 3 is a front view of the rear traveling member and the holder array member in the plate material conveying device.

FIG. 4A is a plan view of a state of the holder array member, and FIG. 4B is a plan view of a different state of the holder array member.

FIGS. 5A, 5B, and 5C are diagrams showing different types of plate material holders.

FIG. 6A is a side view showing a state of a plate material separating plate material holder and a peripheral portion thereof, and FIG. 6B is a side view showing a different state of the plate material separating plate material holder and the peripheral portion thereof.

FIG. 7 is a bottom view showing a support structure for a positioning plate material holder.

FIG. 8A is a side view of an example of the configuration of a gripper, FIG. 8B is a front view of the gripper, FIG. 8C and FIG. 8D are diagrams illustrating operation of the gripper.

FIGS. 9A to 9C are plan views of the holder array member holding different plate materials.

FIG. 10A is a plan view showing that a remainder material is gripped by the grippers, and FIG. 10B is a side view showing that the remainder material is gripped by the grippers.

FIG. 11 is a plan view showing that an example of the remainder material is gripped by four grippers.

FIG. 12 is a plan view showing that another example of the remainder material is gripped by the four grippers.

FIG. 13 is a diagram showing that during carrying-out, the remainder material is gripped by the grippers only at one end thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present invention will be described with reference to FIGS. 1 to 13. FIG. 1 is a perspective view of a plate material processing system as a whole including a plate material processing machine 1, a plate material conveying device 2, a pallet 9 and a plate material transport vehicle 3 both serving as a plate material placement portion, and a plate material stocker 4. The plate material processing system further includes a plate material carry-in device (not shown in the drawings) that carries a raw plate material W0 into the plate material processing machine 1. However, description of the plate material carry-in device is omitted. The plate material processing machine 1 and the plate material conveying device 2 are controlled by a computerized processor control device and a computerized conveyance control device (not shown in the drawings), respectively, according to respective control programs.

The plate material processing machine 1 provides the function of cutting out a plurality of product plate materials W from the raw plate material W0 on a table 5 by punching or the like. The plate material processing machine 1 is composed of a punch press, a laser processor, or the like. In this example, the plate material processing machine 1 is a punch press and includes a processing portion 7 that elevates and lowers a punch tool (not shown in the drawings) with respect to a die tool (not shown in the drawings) for processing, and a plate material feeding mechanism 8 that moves the raw plate material W0 forward and backward (Y direction) as well as rightward and leftward (X direction) on the table 5.

The plate material stocker 4 is a device that lays the product plate materials W processed by the plate material processing machine 1, on the pallet 9 in a stack. The plate material stocker 4 has a large number of shelves 4 a on which the respective pallets 9 are placed. The plate material stocker 4 is configured such that on any of the shelves 4 a, the pallet 9 can move forward and backward between a plate material placement position located in the rear of the system in the figure and a storage position to which the pallet 9 moves forward from the plate material placement position.

In the present embodiment, the plate material conveying device 2 carries out the product plate material W processed by the plate material processing machine 1, to the pallet 9 or the plate material transport vehicle 3. The plate material conveying device 2 further carries out a remainder material Ws (FIG. 11) resulting from processing, to, for example, a position adjacent to a standby position of the plate material transport vehicle 3 or a remainder material yard that is a position shared by the plate material transport vehicle 3. The plate material conveying device 2 includes two tracks 11, 12 installed parallel to each other between the plate material processing machine 1 and a stop position of the plate material transport vehicle 3 and directed in a lateral direction, and a first traveling member 13 and a second traveling member 14 which can travel independently along the respective tracks 11, 12.

The two tracks 11, 12 are coupled and integrated together at the laterally opposite ends thereof. The two tracks 11, 12 are supported by a lateral pair of forward and backward moving frames 16. Each of the forward and backward moving frames 16 is movable along a forward and backward movement rail 18. The forward and backward moving frame 16 can be moved forward and backward by a forward and backward movement driving source (not shown in the drawings). The forward and backward movement driving source includes, for example, a servo motor and a conversion mechanism such as a ball screw which converts rotation of the servo motor into linear operation.

FIG. 2 is a side view of the traveling members 13, 14. FIG. 3 is a front view of the traveling member 14. The traveling members 13, 14 are provided on the tracks 11, 12, respectively, so as to travel freely via guide members (not shown in the drawings). Each of the traveling members 13, 14 is self-propelled by a traveling driving source (not shown in the drawings) such as a servo motor. The guide member is, for example, a linear roll bearing or a guide roller and is interposed between a base portion 24 of each of the traveling members 13, 14 and the corresponding one of the tracks 11, 12.

The traveling members 13, 14 have holder array members 19, 20, respectively, which hold a plate material. The holder array members 19, 20 have plate material holder support frames 21, 22, respectively. Each of the plate material holder support frames 21, 22 supports a plurality of plate material holders 23A, 23B, 23C and a gripper 60.

The holder array member 19 (20) can be elevated and lowered with respect to the base portion 24 of the traveling member 13 (14). In the present embodiment, a vertically long elevating and lowering member 25 is fitted in the base portion 24 so as to elevate and lower freely. The plate material holder support frame 21 (22) is attached to the lower end of the elevating and lowering member 25 via a tilting mechanism 26. The elevating and lowering member 25 is elevated and lowered by an elevating and lowering driving source (not shown in the drawings). The elevating and lowering driving source may be provided separately from the traveling member 13 (14) or the base portion 24 itself may be the elevating and lowering driving source.

The tilting mechanism 26 pivotally moves and tilts the holder array member 19, 20 around a pivotal center shaft 27 (FIG. 3) that faces a front-back direction. As shown in FIG. 3, the pivotal center shaft 27 is rotatably supported at the lower end of the elevating and lowering member 25 by a bearing (not shown in the drawings). The plate material holder support frame 22 (21) is fixed to the pivotal center shaft 27. A sector gear 28 is integrally attached to the pivotal center shaft 27. A circular gear 29 meshes with the sector gear 28. The circular gear 29 is provided on the elevating and lowering member 25. The circular gear 29 is rotated by a rotation driving source (not shown in the drawings) to pivotally move the holder array member 20(19) around the center shaft 27. FIG. 3 shows only the tilting mechanism 26 of the holder array member 20. The tilting mechanism 26 of the holder array member 19 has the same configuration.

As shown in FIG. 4, the holder array members 19, 20 are composed of fixed portions 19 a, 20 a and movable portions 19 b, 20 b, respectively. Each of the movable portions 19 b, 20 b can change the position thereof with respect to the corresponding one of the fixed portions 19, 20 between a proximate position shown in FIG. 4A where the movable portion 19 b, 20 b is close to the fixed portion 19, 20 and a separate position shown in FIG. 4B where the movable portion 19 b, 20 b is separate from the fixed portion 19, 20. Specifically, the plate material holder support frames 21, 22 have frame main bodies 21 a, 22 a, respectively, and turning frames 21 b, 22 b, respectively, which are turnable in a substantially horizontal direction with respect to the frame main bodies 21 a, 22 a. The frame main bodies 21 a, 22 a correspond to the fixed portions 19 a, 20 a of the holder array members 19, 20, respectively. Furthermore, the turning frames 21 b, 22 b of the plate material holder support frames 21, 22 correspond to the movable portions 19 b, 20 b of the holder array members 19, 20. The frame main body 21 a, 22 a and turning frame 21 b, 22 b of the plate material holder support frame 21, 22 supports the plate material holders 23A, 23B, 23C.

When placed in the proximate position, the turning frame 21 b of the plate material holder support frame 22, which corresponds to the movable portion 19 b of the holder array member 19, is positioned behind and on the left side of the entire holder array member 19. The turning frame 21 b is pivotally movably supported at the left end thereof serving as a pivotal support point 31. The turning frame 21 b is pivotally moved around the pivotal support point 31 by expanding and contracting a movable portion pivotally-moving air cylinder 32. The separate position (FIG. 4B) corresponds to a state in which the turning frame 21 b in the proximate position (FIG. 4A) has been pivotally moved through 90 degrees in the direction of arrow A1. Furthermore, when placed in the proximate position, the turning frame 22 b of the plate material holder support frame 22, which corresponds to the movable portion 20 b of the holder array member 20, is positioned in front of and on the right side of the entire holder array member 20. The turning frame 22 b is pivotally movably supported at the right end thereof serving as a pivotal support point 33. The turning frame 22 b is pivotally moved around the pivotal support point 33 by expanding and contracting a movable portion pivotally-moving air cylinder 34. The separate position (FIG. 4B) corresponds to a state in which the turning frame 22 b in the proximate position (FIG. 4A) has been pivotally moved through 90 degrees in the direction of arrow A2.

The plate material holders 23A to 23C suck and hold a plate material. The plate material holders 23A, 23B are of an air suction type, and the plate material holder 23C is a magnet type. As shown in FIG. 5A, the air suction type plate material holder denoted by reference numeral 23A is made up of a bunch of a plurality of suction pipes 23 b individually connected to a vacuum source via an air path composed of an air hose 23 a or the like. The plate material holder 23A is characterized by being able to suck and hold a suction target such as a plate material even if a part of the plate material holder 23A fails to contact with the suction target. As shown in FIG. 5B, the air suction type plate material holder denoted by reference numeral 23B includes a pad 23 c composed of an elastic material. The interior of the pad 23 c is connected to the vacuum source via the air path composed of the air hose 23 a or the like. The plate material holder 23B is characterized by exerting a stronger suction force than the plate material holder 23A. The plate material holders 23A, 23B hold and release the plate material in response to opening and closing of a throttling portion provided in the air path. As shown in FIG. 5C, the magnet type plate material holder 23C has a suction portion 23 d composed of an electromagnet. The suction portion 23 d attracts the plate material that is an iron plate. The plate material holder 23C holds and releases the plate material in response to turning-on and-turning off of electricity applied to the suction portion 23 d.

Furthermore, the plate material holders 23A to 23C are partitioned according to the locations where the holder array members 19, 20 are arranged. That is, in FIG. 4A, the plate material holders 23A, 23B, 23C within the range denoted by reference numeral 35 are common plate material holders arranged in association with one another by both holder array members 19, 20. The plate material holders 23B within the range denoted by reference numeral 36 are specific plate material holders provided exclusively in the respective holder array members 19, 20.

When the turning frames 21 b, 22 b of the plate material holder support frames 21, 22, which correspond to the movable portions 19 b, 20 b of the holder array members 19, 20, are in the proximate position (FIG. 4A), the relative positions and types of the common plate material holders 23A, 23B, 23C are the same for both holder array members 19, 20. Specifically, in both holder array members 19, 20, the common plate material holders 23A, 23B, 23C are provided in two rows that are adjacent to each other in the front-back direction so that for each of the common plate material holder 23A, 23B, 23C, a plurality of plate material holders are provided in each row. The front row extends slightly further leftward than the rear row. The extending portion serves as a small-object holding portion 37. The small-object holding portion 37 includes the air suction type plate material holder 23A, composed of the bunch of a plurality of suction pipes 23 b, and the magnet type plate material holder 23C. As shown in FIG. 4A, when the movable portions 19 b, 20 b of the holder array members 19, 20 are in the proximate position, a virtual outer peripheral shape (not shown in the drawings) enclosing the outer periphery of each of the holder array members 19, 20 appears, in a plan view, substantially like a rectangle with long sides extending in the X direction (traveling direction).

When the turning frames 21 b, 22 b of the plate material holder support frames 21, 22, which correspond to the movable portions 19 b, 20 b of the holder array members 19, 20, are in the separate position (FIG. 4B), the movable portions 19 b, 20 b are partly positioned in traveling areas R1, R2 of the adjacent holder array members 19, 20, respectively. The traveling areas R1, R2 as used herein refer to areas through which the respective holder array members 19, 20 with the movable portions 19 b, 20 b in the proximate position travel and pass. As shown in FIG. 4B, in this state, a virtual outer peripheral shape (not shown in the drawings) enclosing the outer periphery of the array of the holder array members 19, 20 appears, in a plan view, substantially like a rectangle with long sides extending in the X direction (traveling direction). The virtual rectangle enclosing the outer periphery of both holder array members 19, 20 with the movable portions 19 b, 20 b in the separate position has larger long and short sides than the above-described virtual rectangle independently enclosing each of the holder array members 19, 20 with the movable portions 19 b, 20 b in the proximate position. The substantially rectangular outer peripheral shape enclosing the outer periphery of the array of both holder array members 19, 20 means that the arrangement of the plate material holders 23A, 23B, 23C is point-symmetric with respect to a symmetry center point 0. The symmetry center point 0 is positioned between the holder array members 19, 20.

Those of the specific holder array members 23B of the holder array member 19 which are denoted by reference numeral (1) are plate material separating plate material holders which, when the uppermost one of stacked plate materials is sucked and held, separate the uppermost plate material from the other plate materials. As shown in FIG. 6, each of the plate material separating plate material holders 23B(1) is supported by a support member 41 via a support rod 40. A pin 42 projects from the laterally opposite ends of the support member 41. The pin 42 is slidably fitted in slots 43 formed in the frame main body 21 a of the plate material holder support frame 21. The slots 43 are inclined so that the front side thereof is lower than the rear side thereof. A swinging member 44 is swingably attached to the pin 42. A piston rod 45 a of a plate material separating air cylinder 45 is fixed to the swinging member 44.

The support rod 40 can be extended from and retracted into the support member 41. The support rod 40 is biased by a return spring 46 so as to project from the support member 41. Where, upon holding the plate material W, the plate material holder 23B(1) is subjected to a reaction force from the plate material W, the support rod 40 is retracted into the support portion 41 against the elastic repulsion force of the return spring 46. Thus, the reaction force is absorbed. A buffer mechanism composed up of the support rod 40 and the return spring 46 is also provided in the other plate material holder.

When the uppermost one of the stacked plate materials is sucked and held independently by the holder array member 19 or through the cooperation of the holder array members 19, 20, the uppermost plate material is separated from the other plate materials as follows. First, as shown in FIG. 6A, the plate material holder 23B(1) sucks the front end of the uppermost plate material W. In this state, the piston rod 45 a of the plate material separating air cylinder 45 is retracted. Then, the pin 42 is guided through the slot 43 to move the support member 41 obliquely upward and backward while tilting the support member 41 backward. Thus, as shown in FIG. 6B, the plate material holder 23B(1) is raised with the front side thereof floating to separate the front end of the uppermost plate material W from the other plate materials W.

Those of the specific plate material holders of the holder array member 19 which are denoted by reference numeral (2) are positioning plate material holders that position the plate material W to be placed on the table 5 of the plate material processing machine 1. As shown in FIG. 7 that is a bottom view of an essential part of the holder array member 19, a first support member 47 supporting the positioning plate material holder 23B(2) is supported by a pair of front-back slide rods 48 and biased forward by front-back absorption springs 49, 49. Furthermore, a second support member 50 supporting the front-back slide rods 48 and the front-back absorption springs 49, 49 are supported by a pair of lateral slide rods 51 and biased leftward by lateral absorption springs 52. The lateral slide rods 51 and the lateral absorption springs 52 are supported on the frame main body 21 a of the plate material holder support frame 21.

Besides the plate material holders 23A, 23B, 23C, the grippers 60 are installed on the frame main body 21 a, 22 a and the turning frame 21 b, 22 b of the plate material holder support frame 21, 22. Specifically, as shown in FIG. 4, one gripper 60 is installed on the left end side of the frame main body 21 a of the plate material holder support frame 21 on the first traveling member 13 side. The gripper 60 is postured such that the opening thereof faces the central side of the plate material. On the turning frame 21 b of the plate material holder support frame 21, one gripper 60 is installed at a position located a predetermined distance away from the gripper 60 on the frame main body 21 a and toward the second traveling member 14 when the turning frame 21 b is in the separate position after turning as shown in FIG. 4B. The gripper 60 is postured such that the opening thereof faces the central side of the plate material. Furthermore, one gripper 60 is installed on the right end side of the frame main body 22 a of the plate material holder support frame 22 on the second traveling member 14 side. The gripper 60 is postured such that the opening thereof faces the central side of the plate material. On the turning frame 22 b of the plate material holder support frame 22, one gripper 60 is installed at a position located a predetermined distance away from the gripper 60 on the frame main body 22 a and toward the first traveling member 13 when the turning frame 22 b is in the separate position after turning as shown in FIG. 4B. The gripper 60 is postured such that the opening thereof faces the central side of the plate material. In this case, the direction of the opening of each of the grippers 60 is fixed but may vary provided that the gripper opening is allowed to at least face the central side of the plate material. Furthermore, in this case, the end of the plate material W is gripped by a total of four grippers 60. However, the number of grippers 60 may be at least 4, for example, at least 5 or 6. Alternatively, the support of the grippers 60 by the frame main bodies 21 a, 22 a may be omitted. For example, a total of four grippers 60 may be supported solely by the turning frames 21 b, 22 b.

FIGS. 8A and 8B are a side view and a front view showing an example of the configuration of the gripper 60. The gripper 60 has L-shaped lower jaw 61 hanging from the plate material holder support frame 21, 22 so that the lower jaw 61 can be elevated and lowered by an elevating and lowering cylinder 64, and an upper jaw 62 located opposite a horizontal piece portion 61 a of the lower jaw 61 so as to be freely elevated and lowered. A frame 65 supporting an upper jaw elevating and lowering cylinder 63 is provided on a vertical piece portion 61 b of the lower jaw 61. The upper jaw 62 is drivingly elevated and lowered opposite the horizontal piece portion 61 b of the lower jaw 61 by the upper jaw elevating and lowering cylinder 63. Thus, as shown in FIGS. 8C and 8D, the end of the plate material W is gripped by the upper jaw 62 and the horizontal piece portion 61 a of the lower jaw 61. Furthermore, a stopper 66 is provided at one end of the vertical piece portion 61 b of the lower jaw 61 so as to be adjustably moved forward and backward in a direction in which the horizontal piece portion 61 a projects. The stopper 66 regulates the amount by which the plate material Ws enters the opening of the gripper 60. When the plate material holders 23A, 23B, 23C hold the plate material, the grippers 60 are elevated and retracted by the elevating and lowering cylinder 64 to a height position where the grippers 60 avoid obstructing the operation of holding the plate material. The plate material gripped by the grippers 60 grips is the remainder material Ws (FIG. 11) resulting from cutting-out of the product W from the raw plate material W0 as shown in FIG. 11. The remainder material Ws has a hole resulting from the cutting-out of the product W. Thus, the remainder material Ws often fails to be held by the plate material holders 23A, 23B, 23C based on the suction. However, even the remainder material Ws can be reliably gripped by the grippers 60. The grippers 60 may grip the product W or the raw plate material W0.

The plate material is positioned by using a work piece holder (not shown in the drawings) and an end locator (not shown in the drawings) provided on the table 5; the work piece holder serves as a positioning reference in the front-back direction of the plate material, and the end locator serves as a positioning reference in the lateral direction. Once the plate material is carried onto the table 5, all the plate material holders 23A, 23B, 23C are allowed to stop the suction to place the plate material on the table 5. Then, only the positioning plate material holder 23B(2) holds the plate material. The lateral pair of forward and backward moving frames 16 is moved forward. Once the plate material comes into abutting contact with the work holder, the movement of the forward and backward moving frames 16 is stopped. When the forward and backward moving frames 16 have moved excessively, the excessive movement is absorbed by the front-back absorption springs 49. Thus, the front-back (X direction) positioning of the plate material is completed. Then, the traveling member 13 is moved leftward. Once the plate material comes into abutting contact with the end locator, the movement of the traveling member 13 is stopped. When the traveling member 13 has moved excessively, the excessive movement is absorbed by the lateral absorption springs 52. Thus, the lateral (Y direction) positioning of the plate material is completed. The front-back (X direction) positioning may be performed after the lateral (Y direction) positioning has been performed. Alternatively, the lateral (Y direction) positioning and the front-back (X direction) positioning may be simultaneously performed.

The specific plate material holders 23B(3) of the holder array member 20 are used to convey large-sized plate materials. The specific plate material holders 23B(1), 23B(2) of the holder array member 19 are used to convey large-sized plate materials.

In the plate material conveying device 2 configured as described above, the forward and backward moving frames 16 move forward and backward along the forward and backward movement rail 18. The traveling members 13, 14 travel along the tracks 11, 12. The holder array members 19, 20 elevate and lower to convey the product plate material W held on the plate material processing machine 1, to the pallet 9 or the plate material transport vehicle 3, serving as the plate material placement portion. The holder array members 19, 20 hold the product plate material W as shown in FIGS. 9A, 9B, 9C.

That is, as shown in FIG. 9A, a small product plate material W1 is held by plate material holders 23A, 23C of the small object holding portion 37 of the holder array member 19 (20). This is because the plate material holders 23A, 23C in the small object holding portion 37, located at the left end of the front row, easily prevents the holder array member 20 from interfering with the plate material processing machine 1. As shown in FIG. 9B, a medium-sized product plate material W2 is held by the plate material holders 23A, 23B, 23C on the holder array member 19 (20) with the movable portion 19 b (20 b) placed in the proximate position. FIGS. 9A and 9B show that the product plate materials W1, W2 are held by the holder array member 19. However, the above description also applies to the holder array member 20 holding the product plate materials W1, W2.

Furthermore, for a large product plate material W3, as shown in FIG. 9C, the two traveling members 13, 14 are stopped on the tracks 11, 12 in juxtaposition (only the base portions 24 of the traveling members 13, 14 are shown). The movable portions 19 b, 20 b of the holder array members 19, 20 are shifted to the separate position. Both holder array members 19, 20 then hold the product plate material W3. In this manner, the holder array members 19, 20 of the two traveling members 13, 14 hold the common plate material W3. Then, even the large plate material W3 can be held by the plate material holders 23A, 23B, 23C in the vicinity of the edge of the plate material. The plate material W3 can thus be stably conveyed. When the movable portions 19 b, 20 b are in the separate position, the array of the plate material holders 23A, 23B, 23C on both holder array members 19, 20 is shaped substantially like a rectangle. This is suitable for conveying the product plate material W3. The relative positions of the traveling members 13, 14 are shifted in the traveling direction so as to accommodate the size of the product plate material W3.

As described above, various plate materials of different sizes can be efficiently conveyed by selectively performing an individual conveying operation in which the traveling members 13, 14 use the holder array members 19, 20, respectively, to hold and individually convey the relatively small plate materials W1, W2, and a cooperative conveying operation in which the traveling members 13, 14 use the holder array members 19, 20, respectively, to hold and convey the common, large plate material W3.

In the plate material conveying device 2, the two traveling members 13, 14 cooperatively convey the large plate material W3. Thus, the size of the holder array members 19, 20 of the traveling members 13, 14 can be reduced. This enables an increase in the speed of the traveling members 13, 14 and a reduction in time required for acceleration and deceleration. Furthermore, the distance between the tracks 11, 12 can be reduced, thus allowing the whole plate material conveying device 2 to be made compact. When the movable portions 19 b, 20 b of the holder array members 19, 20 are in the proximate position, the two traveling members 13, 14 can pass each other while preventing the holder array members 19, 20 from interfering with each other. Thus, the relatively small plate materials W1, W2 can be conveyed independently by the individual traveling members 13, 14 and simultaneously by both traveling members 13, 14. That is, the relatively small materials W1, W2 can be more efficiently conveyed.

Moreover, when the movable portions 19 b, 20 b are in the proximate position, the arrays of the common plate material holders 23A, 23B, 23C on the holder array members 19, 20 are exactly the same in terms of the relative positions and types of the plate material holders. Thus, plate materials with the same size and shape can be held by the holder array members 19, 20 under the same conditions. Consequently, when the traveling members 13, 14 perform the individual conveying operations, any of the plate materials can be held by each of the holder array members 19, 20 of the traveling members 13, 14. This improves conveyance efficiency. Furthermore, when the array of the plate material holders 23A, 23B, 23C is the same for both holder array members 19, 20, the operation of the plate material holders 23A, 23B, 23C can be controlled in the same manner for both holder array members 19, 20. As a result, the holder array members 19, 20 and the plate material conveying device 2 as a whole can be easily controlled.

The movable portions 19 b, 20 b of the holder array members 19, 20 are turned around the pivotal support points 31, 33, respectively, for repositioning. Thus, the movable portions 19 b, 20 b can be easily switched between the proximate position and the separate position. Furthermore, the movable portions 19 b, 20 b of the holder array members 19, 20 are provided on the opposite sides in the traveling direction. Thus, when the movable portions 19 b, 20 b are in the separate position, the plate material holders 23A, 23B, 23C are arranged over a wide range. Consequently, the holder array members 19, 20 can hold a large plate material.

In the present embodiment, when the movable portions 19 b, 20 b of the holder array members 19, 20 are in the proximate position, the arrangement of the common plate material holders 23A, 23B, 23C on the holder array members 19, 20 is such that the relative positions and types of the plate material holders 23A, 23B, 23C are exactly the same for both holder array members 19, 20. However, the relative positions and types of the plate material holders 23A, 23B, 23C have only to be substantially the same and may vary slightly between the holder array members 19, 20. In terms of percentage, the difference in the number of holder array members between the holder array members is preferably at most 20%, more preferably at most 10% of the total number. In terms of the number of holder array members, the difference may be about 1 or 2. Furthermore, the types and arrangement of the plate material holders 23A, 23B, 23C may vary slightly between the holder array members 19 and 20. Also in this case, in terms of percentage, the number of plate material holders of a different type or in a different arrangement is preferably at most 20%, more preferably at most 10% of the total number. That is, one or two plate material holders may be of a different type or may be differently arranged.

Furthermore, in the present embodiment, the large plate material W3 is conveyed by two traveling members 13, 14. However, the large plate material W3 may be conveyed by three or more traveling members. In this case, the number of tracks may be three or more. Alternatively, at least two traveling members may travel on one track.

Moreover, in the present embodiment, the plate material conveying device 2 is used to carry out the product plate material W from the plate material processing machine 1. However, the plate material conveying device 2 may be used to carry the raw plate material W0 into the plate material processing machine 1.

The remainder material Ws resulting from cutting-out of the product plate material W from the raw plate material W0 may be carried out to the remainder material yard by the plate material holders 23A, 23B, 23C. However, the plate material holders 23A, 23B, 23C may fail to suck the remainder material Ws. In this case, as shown in FIG. 10, the remainder material Ws can be carried out with the grippers 60 gripping the remainder material Ws at the opposite ends thereof in the transfer direction. That is, in this case, as in the case of the conveyance of the product plate material W3 by the plate material holders 23A, 23B, 23C, shown in FIG. 9C, the two traveling members 13, 14 are stopped on the tracks 11, 12, respectively, in juxtaposition. Furthermore, the movable portions 19 b, 20 b (turning frames 21 b, 22 b) of the holder array members 19, 20 are shifted to the separate position. Then, with the four grippers 60 gripping the remainder material Ws at the opposite ends thereof in the transfer direction, the two holder array members 19, 20 cooperatively carry out the remainder material Ws onto a pallet 70 in the remainder material yard.

When the common remainder material Ws is gripped by a total of four grippers 60 on the two traveling members 13, 14 as described above, each of the opposite ends of the plate material Ws in the transfer direction can be gripped by at least two grippers 60 with a sufficient separation distance maintained between the grippers 60. Thus, the large remainder material Ws can be stably carried out. When the movable portions 19 b, 20 b (turning frames 21 b, 22 b) are in the separate position, the four grippers 60 are positioned substantially in the respective corners of the remainder material Ws. This arrangement is suitable for carrying out the large remainder material Ws, which is rectangular. Where the remainder material Ws has a small width dimension, then during carrying-out to the remainder material yard, the remainder material Ws can be gripped at the opposite ends thereof in the transfer direction by, for example, the gripper 60 on the frame main body 21 a of the holder array member support frame 21 on the first traveling member 13 side and the gripper 60 on the turning frame 22 b of the holder array member support frame 22 on the second traveling member 14 side.

It is assumed that the inside of the remainder material Ws is cut out and that during carrying-out, the remainder material Ws is gripped only at one end thereof by the gripper 60 as shown in FIG. 13. Then, where a bridge Wsa of the remainder material Ws has a branch portion Wsa1 as shown in FIG. 12, when the remainder material Ws is conveyed to the remainder material yard and then stacked on top of other remainder materials Ws, the remainder material Ws may be caught on the carried out remainder materials Ws. In the present embodiment, during carrying-out, the remainder material Ws can be gripped at the opposite ends thereof in the transfer direction by the four grippers 60. This prevents the remainder material Ws from being caught as described above. The remainder material Ws can thus be smoothly carried out.

As described above, the first traveling member 13 and the second traveling member 14 travel to convey the remainder material Ws to the remainder material yard and then stack the remainder material Ws on top of the other remainder materials Ws. This operation is performed according to the control program set in the conveyance control device (not shown in the drawings).

While the present invention has been described with respect to preferred embodiments thereof, it will be apparent to those skilled in the art that the disclosed invention may be modified in numerous ways and may assume many embodiments other than those specifically set out and described above. Accordingly, it is intended by the appended claims to cover all modifications of the present invention that fall within the scope of the invention. 

1. A plate material conveying device characterized by comprising a plurality of tracks, and a first traveling member and a second traveling member which are provided on the respective tracks so as to travel freely along the respective tracks, and in that: each of the traveling members has a plate material holder support frame supporting plate material holders sucking and holding a plate material, and the plate material holder support frame has a frame main body and a turning frame which is turnable in a substantially horizontal direction with respect to the frame main body and which is turnable to a position where the supported plate material planarly overlaps the adjacent track, and in that each of the turning frames has a gripper gripping an end of the plate material, and grip openings of the grippers of the first traveling member and the second traveling member are configured to face a central side of the plate material.
 2. The plate material conveying device according to claim 1, characterized in that the plate material is a remainder material with inside thereof cut out, and the first traveling member and the second traveling member travel to convey the plate material that is the remainder material to a remainder material yard and then stack the remainder material on top of other remainder materials.
 3. The plate material conveying device according to claim 1, characterized in that the gripper is provided on the frame main body of the plate material holder support frame of each of the traveling members, and the plate material is gripped by at least a total of four grippers provided on the frame main body and the turning frame of the plate material holder support frame of each of the traveling members. 